I know how to detect clicks and touches on the views, and i know how to make menus appear when they hit the menu key. My phone also has a little ball like button that you can press down on. How would an activity capture this event, say if you wanted to use it for confirmation of something, like a move. they touch the screen to indicate a move but i want a menu option of confirm move and if they chose it they would touch the screen for moves but click that ball down on phone to confirm and I'd send the move.

is this an on click listener? if so what event is it?
what is that button called? i cant google it because i google button and all i get is pages on the android button that can be added with code to pages.

Also whats the back or dismiss button called? How could i tell if they backed out of the program? If so i want to close it perhaps. better than it never closing like now unless they go to task killer app :)